Forced draft vent assembly



March 4, 1969 wm R 3,431,056

FORCED DRAFT VENT ASSEMBLY Filed May 19, 1967 Sheet I of 2 ZNVENTOR. 00mm E. mNEG/MDNER Mania 8 BY wwwwwww/t m March 1969 o. E. WINEGARDNER 3,

FORCED DRAFT VENT ASSEMBLY Filed May 19, 1967 Sheet 3 of a IN VENTOR. DONALD E. Wmsennnusk United States Patent O 3 Claims ABSTRACT OF THE DISCLOSURE A forced draft vent assembly for a gas log including a conduit and a swingably mounted sail positioned in the conduit and sensing the movement of air through the conduit. The sail is connected to a variable resistor which controls the speed of an electric motor driving the air moving impeller. In one embodiment the impeller is a blower downstream of a hanging sail while in another embodiment the impeller is a propeller upstream of an upright spring mounted sail.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to flue vent arrangements.

Description of the prior art Frequently it is desired to use a gas fireplace in an apartment which may have several stories. If the apartment is already in existence, obviously the expense, appearance and possible loss of living space involved in building a conventional chimney are undesirable. Even if the apartment is not yet constructed, some means should be provided for moving the products of combustion away from the gas fireplace and the means provided should not be subject to gusts of wind and weather outside the building. Various fluid flow control or sensing arrangements have been devised and are known in the art such as the apparatus shown in US. Patents 3,106,175 to Anderson, 3,193,640 to Mineck, 3,148,254 to Clason and 3,303,305 to Lemmons. These arrangements are not satisfactory to solve the problem of moving the products of combustion of a gas fireplace rapidly and inexpensively and in an aesthetically pleasing manner away from the fireplace out of the apartment. It is also desirable that the flue vent arrangement for the gas fireplace be capable of being easily and quickly repaired without the necessity of the servicemen working outside of the building, possibly high in the air above the ground.

SUMMARY OF THE INVENTION One embodiment of the invention might include a flue vent arrangement comprising a conduit having an input end and an output end, an impeller in said conduit arranged to move gases through said conduit from said input end to said output end, an electric motor driving said impeller, a sail positioned in said conduit, control means for said electric motor arranged to speed up and slow down said electric motor in response to the position of said sail, said control means being arranged to speed up said electric motor when the air flow through said conduit decreases causing said sail switch to move in one direction and to slow down said electric motor when the air flow through said conduit increases causing said sail switch to move in the opposite direction.

One object of this invention is to provide an improved flue vent arrangement.

A further object of this invention is to provide a flue vent arrangement of simple construction which is economical to manufacture.

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Another object of this invention is to provide a flue vent arrangement capable of maintaining a relatively constant draft even when the outside atmosphere is windy and stormy.

Still a further object of the invention is to provide a flue vent arrangement which is easily and quickly repaired.

Related objects and advantages will become apparent as the description proceeds.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view of a flue vent arrangement embodying the present invention.

FIG. 2 is a longitudinal section partially in elevation taken through the flue vent arrangement of FIG. 1.

FIG. 3 is an enlarged vertical section taken along the line 3-3 of FIG. 2 in the direction of the arrows.

FIG. 4 is a schematic electrical diagram of the circuit of the illustrated device.

FIG. 5 is a section similar to FIG. 2 of an alternative embodiment of the invention.

FIG. 6 is an electrical schematic diagram of the circuit of the device of FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now more specifically to the drawings, there is illustrated a flue vent arrangement 10" which includes a conduit 11. The conduit 11 is made up of telescoping sections of conventional furnace ducts. The conduit 11 has mounted thereon a rectangular frame 12 which is mounted to the wall 15 by means of a flanged rectangular member 16. The flanged rectangular member 16 is secured to the wall 15 so as to line an opening 17 extending through the wall. The member 16 also mounts a housing 20 which is closed at its upper and outer portions so as to form a shield for the outwardly projecting portion 21 of the conduit 11. The housing 20 does have a downwardly facing opening 22.

An electrical motor 25 is mounted on the conduit 11 by means of a channel 26. The motor 25 has an output shaft 27 to which is mounted a partition 30 which is fixed to and divides a blower wheel 31 into two portions 32 and 35. The portion 32 of the blower wheel functions to receive the air from the leftward portion of the conduit 11 as viewed in FIG. 2 and to move it outwardly and downwardly through a downwardly facing opening 36 in the conduit 11, thence out through the downwardly facing opening 22. The portion of the blower wheel 31 functions to move air leftwardly as viewed in FIG. 2 through an opening 37 in the conduit across the motor 25 so as to cool the motor and then moves the air outwardly through the opening 36 in the conduit 11, thence downwardly through the opening 22 in the housing 20. The blower wheel 31 has a plurality of conventional inclined blower blades 38 which move the air.

It can be appreciated that as suggested in FIG. 1 the conduit 11 can be quickly removed from the housing 20 so as to permit maintenance and repair on the electric motor 25. Such removal involves merely the disconnecting of suitable bolts and screws holding the conduit 11 within the housing 20 and securing it to the wall 15.

Referring to FIG. 3, the motor 25 is controlled by a sail 40 which is fixed to and depends from a shaft 41. The shaft 41 is rotatably mounted upon the conduit 11 by means of Teflon bearings 42. Fixed to the shaft 41 is an inertia wheel 45 which prevents the sail 40 from responding too quickly to quick gusts of air such as, for example, might come in through the opening 22 upwardly and act against the sail 40.

Fixedly mounted upon the conduit 11 is a motor control which includes a variable resistor 51. The shaft 41 is coupled to the variable resistor 51 so that as the sail 40 pivots and changes position such as, for example, to the dotted line position illustrated in FIG. 2, the resistance of the variable resistor 51 changes. The control 50 may include a conventional SCR circuit which, while not affecting the voltage provided to the motor 25, does affect the amount of current and the shape of the electrical wave provided to the motor 25. Thus, the motor 25 can be an induction motor and the speed thereof controlled by the variation of the resistance of the variable resistor 51.

Referring to FIG. 4, the control 50 is illustrated schematically as receiving the input lines 53 and as being provided with the output lines 52 which couple the control to the electric motor 25. The variable resistor 51 is also shown as being coupled to the control 50 by the three lines 55. As mentioned, the control 50 may be a conventional SCR control capable of slowing down the motor 25 when the resistance of the variable resistor 51 is changed. Thus, when the sail 40 swings rightwardly as viewed in FIG. 2, the motor 25 tends to slow down while the motor is speeded up when the sail 40 swings leftwardly. Preferably a gage pressure below atmosphere of .01 inch of water is preferred within the conduit 11 although obviously different type installations may be better adapted to different type pressures within the conduit 11.

Referring now to FIG. 5, there is illustrated a flue vent arrangement 100 which includes a conduit 101 mounted so as to extend through an opening 102 in a building wall 103. Within the conduit 101 is provided a propeller 105 which is driven by a motor 106 connected to the propeller 105 through a bevel gear coupling 107. A sail 110 is positioned between the propeller 105 and the outlet opening 111 of the conduit 101. The sail 110 is pivotally mounted on the conduit 101 and 112 and is coupled to a variable resistor 115 so that the position of the sail 110 also changes the position of the variable resistor 115. The said 110 is normally held in an upright position by a spring 116 which is connected between the arm 117 and the wall 103.

The arrangement of FIG. also includes a limit switch 120 which is operated by the arm 117 which mounts the sail 110. The limit switch 120 is in the circuit illustrated in FIG. 6 and controls electrical energization of the gas valve solenoid 121. The gas valve solenoid 121 is in series with a switch 122 and the secondary 125 of a transformer 126 as well as the limit switch 120. The transformer 126 steps down the voltage from the house power at 115 volts across the primary 127 to the secondary voltage of 24 volts across the secondary 125. The purpose of the limit switch 120 is to maintain the gas valve in a closed condition until a suitable draft has been accomplished in the conduit 101. When this occurs, of course, the sail 110 is moved rightwardly so that the lever 117 moves away from the limit switch 120, thus permitting gas to flow through the gas valve. The gas valve solenoid 121 is a slow acting solenoid (i.e. slow to open and slo v to close) to prevent any quick gusts of wind from affecting the gas valve appreciably. The further switch 122 is a heat operated switch which functions to shut off gas flow through the gas valve when the heat at the upper portion 130 of the conduit 101 increases above a certain temperature.

It will be evident from the above description that the present invention provides an improved flue vent arrangement. It will further be evident that this invention provides a flue vent arrangement of simple construction and which is economical to manufacture. It will also be understood from the above description that the flue vent arrangement of this invention is capable of maintaining a relatively constant draft even when the outside atmosphere is windy and stormy.

While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention and the scope of the claims are also desired to be protected.

The invention claimed is:

1. A flue vent arrangement comprising a conduit having an input end and an output end, an impeller in said conduit arranged to move gases through said conduit from said input end to said output end, an electric motor driving said impeller, a sail positioned in said conduit, control means for said electric motor arranged to speed up and slow down said electric motor in response to the position of said sail, said control means being arranged to speed up said electric motor when the air flow through said conduit decreases causing said sail switch to move in one direction and to slow down said electric motor when the air flow through said conduit increases causing said sail switch to move in the opposite direction, said conduit extending in a horizontal direction, a building wall, said conduit extending through said building wall and having said output end positioned on the outside of said building, said impeller being a propeller, said sail being spring biased to an upright position and located between said propeller and said output end, a gas valve for supplying gas to a fireplace from which the products are to be exhausted through said conduit, a limit switch arranged to be actuated by said sail when the air flow through said conduit decreases a given amount, and circuit means controlled by said limit switch to shut off said gas valve when said limit switch is actuated by said sail.

2. A flue vent arrangement comprising a conduit having an input end and an output end, an impeller in said conduit arranged to move gases through said conduit from said input end to said output end, an electric motor driving said impeller, a sail positioned in said conduit, control means for said electric motor arranged to speed up and slow down said electric motor in response to the position of said sail, said control means being arranged to speed up said electric motor when the air flow through said conduit decreases causing said sail switch to move in one direction and to slow down said electric motor when the air flow through said conduit increases causing said sail switch to move in the opposite direction, a building wall having an opening therethrough, a housing mounted on the outside of said building over said building opening, said housing having a downwardly facing outlet opening, said conduit being removably mounted on said building wall and extending through said building wall opening into said housing, said electric motor being mounted on said conduit at said outlet end, said impeller comprising a blower wheel mounted on the output shaft of said electric motor, said conduit having a downwardly facing opening registering with the downwardly facing opening of said housing, a partition mounted centrally of said blower wheel and dividing said blower wheel into two blower portions spaced axially of one another, said conduit having a cylindrical shape which closely surrounds said blower wheel except for said downwardly facing conduit opening, one of said blower portions being open at one end to receive air axially from said conduit and to move it out said downwardly facing conduit opening, the other of said blower portions being open at one end to receive air axially from inside said housing and to move it across said motor for cooling thereof thence out said downwardly facing conduit opening.

3. The flue vent arrangement of claim 2 additionally comprising a shaft fixed to said sail, said shaft being pivotally mounted on said conduit in such a manner that said sail hangs swingably in said conduit, an inertia wheel fixed to said shaft, a variable resistor connected to said 5 6 shaft whereby the position to which said sail swings varies 2,561,135 7/1951 Resek 1l0162 the resistance of said variable resistor, said variable rc- 2,704,571 3/1955 Reicheldcrfer 158-422 X sistor forming a part of the control of said electric motor. 3,136,309 6/1964 Martz 126-307 X Remems Cited 5 JAMES w. WESTHAVER, Primary Examiner. UNITED STATES PATENTS 2,348,950 5/1944 Anderson. CL 2,447,405 8/1948 Gaba-r et a1. 110-162 110-162; 200-819 

